Problem: Simplify the expression. $(-2x-1)(5x+7)$
Answer: First distribute the ${-2x-1}$ onto the ${5x}$ and ${7}$ $ = {5x}({-2x-1}) + {7}({-2x-1})$ Then distribute the ${5x}.$ $ = ({5x} \times {-2x}) + ({5x} \times {-1}) + {7}({-2x-1})$ $ = -10x^{2} - 5x + {7}({-2x-1})$ Then distribute the ${7}$ $ = -10x^{2} - 5x + ({7} \times {-2x}) + ({7} \times {-1})$ $ = -10x^{2} - 5x - 14x - 7$ Finally, combine the $x$ terms. $ = -10x^{2} - 19x - 7$